ADR 0016: Use Typer for the unified Loreley CLI

Date: 2026-01-13

Context: Loreley had multiple argparse-based CLIs (loreley/cli.py and an embedded parser in loreley.scheduler.main), which duplicated flags, help text, and exit-code behavior and increased maintenance cost.

Decision: Use Typer as the single CLI framework for loreley and implement all commands (doctor, scheduler, worker, api, ui) as Typer subcommands with a shared global --log-level option.

Decision: Remove CLI parsing from loreley.scheduler.main; keep main(settings=..., once=..., auto_approve=...) as a reusable run function and route module execution through the unified CLI.

Consequences: CLI help output is consistent across commands, global options are shared, and the scheduler runtime is reusable without embedded CLI parsing.